Chili Could Help Control Blood Sugar in Diabetes: Capsaicin from Chili Shown to Control Insulin, Glucose Levels

Capsaicin and dihydrocapsaicin are the active ingredients in chili peppers that give the characteristic chili bite.

The antioxidant properties of chili are already well known, so researcher Dr Kiran Ahuja, decided to investigate capsaicin further.

Dr Ahuja, research fellow at the University of Tasmania School of Human Life Sciences, is studying the effect of capsaicin on the oxidation of LDL cholesterol, and on insulin levels and blood glucose levels after a meal.

“Herbs and spices are natural food additives that contribute significantly to the taste and flavor of our food. In some cultures, they have also been used as medicines and preservatives,” Dr Ahuja said.

“Herbalists have long valued chili – used extensively in South American and Asian cuisine – for its anti-inflammatory and antiseptic effects.”

She is preparing a paper on the results of her five years of research into the metabolic effects of capsaicin.

Chili’s Protective Effect Against Atherosclerosis.

People with diabetes or impaired glucose tolerance are at risk of developing atherosclerosis, (hardening of the arteries). Oxidation of LDL cholesterol is believed to be a cause of the development and progression of this condition, Dr Ahuja said.

Since the antioxidant properties of capsaicin were already known, one experiment introduced capsaicin and dihydrocapsaicin into samples of human serum and the effect on the LDL cholesterol was measured. The samples showed that LDL was protected from oxidation by the capsaicin.

Then Dr Ahuja fed chili paste to 27 adults to see if these results could be replicated when people ate chili.

Chili Meals versus Bland Meals

The subjects were either given bland meals, with no spices of any sort, or meals to which they added a fixed amount of chili paste (55% chili) just before eating.

Adding the paste just before eating ensured all participants consumed exactly the same amount of capsaicin, which might have varied had they cooked their dishes.

There was an almost equal number of men to women, and everyone ate both bland meals and chili meals. Each group ate their designated meal once a week for four weeks.

At the end of that dietary period their blood was tested, then after two weeks’ rest, they ate the other meal once a week for four weeks, and were again tested.

Blood tests taken two hours after eating the last meal showed that the rate of oxidation of LDL cholesterol was significantly lower after the chili meals than the bland meals.

Chili Helps Reduce Blood Glucose After Meals

Dr Ahuja then repeated the chili meal/bland meal crossover trial (all participants ate both bland and chili meals once a week for four weeks), and tested the blood samples for capsaicin’s effect on post-prandial glucose and insulin levels.

The participants were all healthy people aged between 40 and 50. None of them had diabetes or the pre-diabetes condition known as metabolic syndrome or impaired glucose tolerance.

In metabolic syndrome, the pancreas produces more insulin than usual as the insulin is less effective against glucose.

Dr Ahuja’s team found that the chili diet led to a reduction in post-prandial insulin levels and glucose levels in the participants’ blood two hours after the meals.

The capsaicin had assisted the insulin to metabolize the blood sugar, making it available as glycogen to tissues and organs.

Capsaicin from Chili to be Tested on Diabetics

The next step, Dr Ahuja said, would be a clinical trial testing doses of capsaicin on people with early stage Type 2 diabetes.

“We need long-term clinical studies to be really sure that capsaicin could prevent this type of diabetes,” she said. “For people who are producing too much insulin, it might be of benefit. It may well delay the time when they become insulin dependent.”

Enjoy Chili Meals for Antioxidants and Possible Diabetic Benefits

While it was far too early to say for sure that capsaicin from chili would prevent Type 2 diabetes, or delay the onset of insulin-dependence, she said people should still enjoy eating chili for it’s antioxidant content – and great taste.

“It’s not necessary to eat it uncooked,” she said. “ Capsaicin is fat-soluble, so when you fry chili while cooking, it becomes easily available to the body.”